Unfortunately, because place names tend to be particularly ancient, their precise origins and meanings are often very tricky to pin down. Shortfalls and inconsistencies in what little historical evidence is available mean there’s often just as much conjecture and guesswork involved as there is hard fact, and even then some names defy all attempts to explain them.

For instance, despite being one of the most famous cities in the world, no one really knows what “London” means. Instead, theories range from the relatively sensible—perhaps a long-forgotten Welsh word, meaning something like “river-fort” (llyn-din), or “pool on the river” (llyn-dain)—to the downright bizarre, with one idea even suggesting some kind of reference to Luna, the Roman goddess of the Moon. (Shameless plus: there’s more on that in the new book…)

So. The earliest written record of “Britain” that we know about comes from an Ancient Greek explorer and adventurer named Pytheas of Massalia. Sometime around 325BC, Pytheas circumnavigated and explored the entire British Isles, probably becoming the first person in history to do so. He also travelled high enough into northern Europe to describe the Midnight Sun (probably becoming the first person to do so); crossed the Arctic Circle and spotted the outer fringes of the great northern icecap (probably becoming the first person to do so); and was the first explorer from Mediterranean Europe to reach the Baltic Sea by boat. He was, it’s fair to say, a bit of a dude.

Pytheas’s accounts of his journeys were among the most celebrated geographical texts in antiquity, but unfortunately all of his original writings have long since been lost. Everything we know about his travels now comes from the smattering of quotes, extracts, and discussions that later writers and historians—including the great Roman naturalist Pliny the Elder, who keeps cropping up on here—included in their work. But what has survived is Pytheas’s early use of the word “Britain”, which he recorded more than 2,300 years ago as “Bretannike”.

At the time of Pytheas’s visit, Britain would still have been a hodgepodge of different Celtic and pre-Roman tribes and languages. In the far north and west, however, two increasingly dissimilar branches of the ancient Celtic language family were starting to take shape: Goidelic, or “Q-Celtic”, in the far north and northwest (which eventually gave rise to Irish, Manx and Scots Gaelic), and Brythonic, or “P-Celtic”, in the west and southwest (which eventually gave us Welsh, Cornish and Breton).
The nicknames “P” and “Q” refer to the fact that Brythonic Celtic tended to develop a p sound where Goidelic Celtic tended to have a hard q or k sound, and vice versa. We’re dealing with impossibly ancient words here, of course, but you don’t have to look too far to find evidence that this change took place: pick up an atlas or a road map of the British Isles, and you’ll find Pentire, a peninsula on the north coast of Cornwall, and Kintyre, a peninsula in southwest Scotland. Both names literally mean “headland”; both derive from P-Celtic (penn) and Q-Celtic (keann) words meaning “head”; and both are practically identical, except for their initial p and k sounds.

But anyway, back to Pytheas. Based on linguistic evidence like this—and based on what little we know of Pytheas’s route—it’s thought that his “Bretannike”must be derived from some early Brythonic or “P-Celtic” word, suggesting that the people he learned it from originated somewhere around modern-day Wales or southwest England. We can only guess at what this original root word might have been, but from what we know about the Celtic languages, the consensus among etymologists and toponymists (that’s place name researchers to you and me) is that its closest modern descendant is probably an old Welsh word, prŷd, essentially meaning “form”, “image”, or “countenance”. If this presumption is correct, then the ancient Britons would quite literally have been “the people of the forms”, which, it’s again presumed, is an apparent reference to their supposed fondness for war paint and tribal tattoos. There are, admittedly, several rivalling theories here—and historians are undecided about whether these Iron Age Britons tattooed each other or not—but, etymologically at least, there is a strong argument to suggest Britain is quite literally the home of the “tattooed people”.And, appropriately enough, Britain is now apparently the most tattooed nation in Europe. Everything really does come full circle.

_______________________________Hat tips to David Willbe (@DavidWillbe) and Dr Matt Lodder (@mattlodder) for links to the historical arguments for and against Pictish tattoos. Tatt you very much. (Sorry...)

Actually the greeks never called britian Prettanike ..he called the island of britian albion and ireland as Irene . only collectively were both islands called Prettanike not seperately ... , Britian was an invention by the Roman state and julius caesar ;) and there was no q celts in the island of Albion when Pytheas of Massalia was knocking about , q celtic was brought to Northern Albion by the Gaelic-speaking irish people from Ulster, , who eventually Gaelicised the west coast of Pictland, according to the Venerable Bede, by a combination of force and treaty. The inhabitants of Dalriada are often referred to as Scots (Latin Scotti), a name originally used by Roman and Greek writers for the Irish who raided Roman Britain. Later it came to refer to Gaelic-speakers in general, whether from Ireland or elsewhere.The name Dál Riata is derived from Old irish Gaelic. Dál means “portion” or “share” The scottish are Gaelicised from Antrim this is the ancestors of the scottish people .